Most of the suture kits which come in zippered bags are most certainly NOT sterile, though they may be new. If you need a sterile pack, these will come prepacked and SEALED with an expiration date.

Its also a better idea to get the sutures and the instrument pack seperately, since they have different expiry dates to their sterility.

A kit with no knowledge of how to use the kit is useless or at worst dangerous, whereas knowledge without a kit allows you to improvise solutions.